(1) Field of the Invention
The present invention relates to a continuous method for manufacturing thermic lances.
(2) Description of the Prior Art
Thermic lances are made from a steel tube filled with metal wires. At one end, the tube is connected to an oxygen source through a pressure regulator. The oxygen is admitted at the other end when the said other end has been heated up, locally, to approximately 800.degree.-900.degree. C. by any heat source such as torch or a blow lamp.
A strong oxydation reaction of the steel takes place, thus producing a powerful flame with a temperature of approximately 2500.degree. C. The length of the flame is variable, depending on the diameter of the lance and of the oxygen pressure. The produced heat can be used to cut or drill ferrous or non-ferrous material, including cast iron in open air and also possibly under water.
The flame also produces an iron oxide which acts as a melting agent, thus reducing an iron oxide which acts as a melting agent, thus reducing the melting point of concrete or rock, from about 2000.degree.-2500.degree. C. to approximately 1100.degree.-1500.degree. C. This phenomenon causes a pasty melt and elimination of material, which enables the thermic lances to be used to drill or to cut concrete elements and most rocks.
Generally, the method for manufacturing thermic lances comprises the introduction of wires in a discontinous process, that is to say by manual work, in metallic tubes of a limited length. This method is slow and presents all disadvantages of discontinuous process, such as the impossibility to choose variable lengths for the lances important manual efforts and expensive manufacturing. Furthermore, the tubes can only be filled partially compared to the number of wires which could theoritically be filled in the tube.